Both companies are real estate investment trusts that specialize in biotechnology and other life science tenants.

The purchase price consists of about $169 million assumed debt, $133 million in BioMed common stock, and the rest in cash. To help finance the purchase, BioMed Realty said it would sell 15 million shares of stock.

The deal is expected to close in the third quarter of 2013. Wexford Science & Technology will operate as a wholly owned subsidiary, BioMed Realty said.

The Wexford purchase gives BioMed Realty an expanded presence on the East Coast and more academic tenants. Wexford's 1.6 million-square-feet portfolio largely consists of university tenants. They include the University of Pennsylvania Health System, Washington University in St. Louis, and Old Dominion University in Norfolk, Va. These and other existing properties account for about $551 million of the purchase price.

"They've done a very good job of penetrating and supporting and pursuing the university segment," said R. Kent Griffin, BioMed Realty's president and chief operating officer. "That's a piece of our business, but it's all of their business. And we want them to keep doing it as well as they've being doing it."

Wexford could expand to serve university and research properties on the West Coast, Griffin said.

"We can bring that into some of the large markets where we are, like San Diego and San Francisco, and Boston and elsewhere," Griffin said. "San Diego and San Francisco are two of our main markets. To the extent that we can pursue and provide university and research institution support, San Diego's certainly ripe for that type of opportunity."

About $89 million of the purchase price goes to 935,000 of rentable space currently under construction, BioMed Realty said in a press release on the purchase. BioMed Realty said it will cost an estimated $159 million to complete the projects under construction. These projects should all be fully funded by 2014, the company said.

Adding Wexford will boost BioMed Realty's percentage of rents from universities and research institutions from 13 percent of annualized base rents to 18 percent of annualized base rents.